Comments by "mpetersen6" (@mpetersen6) on "Machine Thinking" channel.

  1. And then there are the artifacts from antiquity that defy explanation by archeologists. There are stone blocks in Egypt that display evidence of being machine worked. This was noticed as far back as Flinders Petrie in the late 1800's. And no, I'm not saying aliens or any of that whoo whoo crap. Only that the ancients Egyptians and others had technologies we do not yet know that they had.
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  2. One reason I would think was demand on the part of the buyers or the lack of them. A second was the whole Craft System with Masters, Journeymen and Apprentices. This involved a whole different approach to production of every thing from cloth to metal working to cathedrals. Third was a preceived need. Another reason was the need of the State for the tools of the State. Ships and Arms. Edged weapons were made one at a time by blacksmiths and specialists in armor and blades. They did not need to be interchangeable. Once cannon with standardized bores and small arms became common it was required to produce ever increasing accuracy in manufacture. The first "machine tools" where most likely the ones made for boring cannon to the desired bore diameter. The first known industrial workshop for the production of interchangeable parts was in Southampton or Portsmouth. The Royal Navy set up an operation to make block and tackle for its ships. Before that things like Muskets (the Tower Pattern Musket, ie The Brown Bess) where made to a pattern but where not interchangeable. But once the screw cutting lathe made its appearance the world was changed forever. It brought the Industrial Age with all its benefits and problems. An industrial revolution could of happened 1500 to 2000 years before it did. The Romans are known to have large watermills with multiple mill wheels set up in series so that the water spilling from one mill would turn the wheel of the next. The principles of Gear Wheels were certainly known (that is one thing you need for a screw cutting lathe besides the leadscrew). For centuries the Chinese were the most technologically advanced society on Earth. But the social systems and conditions did not allow such a revolution to burst forth.
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  3. The first real precision industry is one most people wouldn't consider. The manufacturing of pencils required a high degree of precision to become as ubiquitous as the #2 pencil is today. The other thing that aided precision manufacturing was uniform systems of screw pitches and other mechanical components such as gears and splines. While some companies* continued to use their own size's of screws industry eventually settled into the screw systems we use today. In the world of precision machine tools there are some companies that got into the business simply because they needed machines with higher accuracy than were available it the time. Swiss watch companies are an example of this. * Brown and Sharpe were notorious for this
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  4. By taking three pieces and using them to match their surfaces to each other in a process that will produce 3 flat surfaces. Look into Scraping and Surface Plates. https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=12&cad=rja&uact=8&ved=2ahUKEwjVl6Sy8pXeAhVGpFkKHSJfCSsQFjALegQICBAB&url=http%3A%2F%2Fericweinhoffer.com%2Fblog%2F2017%2F7%2F30%2Fthe-whitworth-three-plates-method&usg=AOvVaw1EyJyVi-SijTwVGTuHnL6F https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&cad=rja&uact=8&ved=2ahUKEwjhvbLL8pXeAhUGrVkKHR23BD4QFjAEegQIDBAB&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FSurface_plate&usg=AOvVaw2qWJopr1PnI8fN1YJQit7d Once three flat surfaces have been established they can be used to produce master gages for scraping the ways and sliding elements of a machine. One note here. "Flat" does not mean "Level". "Flat" means the surface is as close to being in one plane as possible.
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  5. ​ @sjb3460  The hard part of cutting Whitworth threads on a lathe is grinding the tools. Not the 55° included angle. But grinding the proper tip radius and the radii that form the proper crown on the top of the thread. Plus some of the Whitworth pitches are not normally found in the Quick Change Gear Boxes of non British lathes. 19 tpi for one. Also it was very common for machine tool builders to have their own special thread pitches. Brown and Sharpe used to use things like 1/4-22 or 1/4-32 (1) for the screws used in their screw machines. Also those really nice Swiss MultiFlex tool posts use things like 7mm, 9mm or other odd sizes not normally found even in the catalogs of industrial supply houses. It's called "buy our parts". 1) I've got a tap for that one
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  6. ​ @tonywilson4713  In the US the standard reference book is Machinery's Handbook. Mine is close to 50 years old and is still useful. In fact it probably has info that is no longer listed in newer editions. We used to make a lot of replacement parts eith gear teeth cut to the Fellows Stub Tooth system. The Pitch Diameter was based on one Diametral Pitch while the overall height of the gear tooth and the OD was derived from the next smaller gear tooth profile. A gear would be expressed as 48T-10/12DP.
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  7. Even if you get a dro. DO NOT DITCH THE TRAV-A-DIAL.
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  8. The Archimedes Screw was the first thing that came to mind
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  9. Wine or olive screw presses existed in the 1st century CE. The Roman's used them. The printing press was an idea just sitting there waiting in the wings. https://www.google.com/url?sa=t&source=web&rct=j&url=https://en.m.wikipedia.org/wiki/Screw_press&ved=2ahUKEwjbrOjE0KvwAhUTAZ0JHTT4BMoQmhMwDXoECAYQAg&usg=AOvVaw34Twd3-D6HFAEhDC0tzDhC
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